Map of provided berths (shapefile)

Map of 1km emissions (sailing PM2.5 shown as example)

Process emissions to raster

Make a raster stack of the emissions by pollutant, and by sailing/berth

Plot of NO2 sailing emissions raster

## [[1]]
## expression(sp.polygons(as(river, "Spatial"), col = "red"))
## attr(,"under")
## [1] FALSE
## attr(,"superpose")
## [1] FALSE
## 
## attr(,"class")
## [1] "layer"   "trellis"

Plot of NO2 berth emissions raster

Process GPS data

Count GPS points in each 10m grid square. Create two rasters, one for ‘at berth’ and one for sailing.

Plot of 10m counted GPS sailing points

Plot of 10m counted GPS berth points

Now divide the number of points in each 10m grid, by the number of points in the surrounding 1000m grid, to find out what percent of the 1000m emissions each 10m grid cell is allocated

Results

So now have ‘berth_grid’ and ‘sailing_grid’ which are 10m cells, and in each cell is a number between 0 and 1, which is the percentage of the 100m cell emissions that belong to that cell. The emissions are a raster stack of 100m resolution. So ‘pull down’ to the 10m grid cell, the amount of emissions from the 1km grid cell, based on the GPS points in that cell divided by the GPS points in the 1km cell.

Plot of 10m PM2.5 sailing emissions

Plot of 10m PM2.5 berth emissions